City bus routes 11 and 26 are replacing their electric capacitance buses next year.

The current buses, said a Shanghai Ba-shi Public Transportation Co director surnamed Zhang, had been in service since the World Expo in 2010.

“The batteries have aged,” Zhang said. “Some of the drivers told me the bus has to stop too frequently to recharge.”

The bus recharges its battery by connecting the pantograph on top of the vehicle with the electric wires above.

Unlike a traditional electric bus, the capacitance bus does not have to link the pantograph with the wire all the time.

“While connected, the pantograph will conduct electricity from the wire to the battery,” one driver said. “This usually takes less than one minute.” Shanghai Daily got on bus 26 yesterday at its starting point on Xinkaihe Road and Zhongshan Road E-2.

The driver pushed a button on the instrument panel to activate the pantograph to recharge at red lights at least five times during its journey.

After getting off at its terminus at Guangyuan Road W. and Hongqiao Road, a male passenger said the bus would stop more frequently in summer because air-conditioning used more electricity.

An elderly woman passenger said she didn’t mind. “It give me more time to get to my seat, some other buses just drive away while I am still walking to the seats,” she said.

Fang Le, a regular passenger on route 26, said he had hardly noticed that the bus was recharging. “But I did wonder why it waited at a stop where no one was boarding the bus or getting off,” Fang said.

Zhang said that even if a bus was fully charged every morning, the battery could not last the whole day. “The first two hours would be fine,” Zhang said. “But then it has to be charged.”

The bus company has told the drivers to charge the battery while waiting at a red light or at a bus stop.

However, sometimes it would take a bit longer for the bus to recharge, and some passengers would complain.

Zhang said there were about 25 electric capacitance buses waiting to be replaced on the routes.

The replacements will be a similar type with a pantograph on top, but the battery would be stronger than in the current buses.